Radio reception apparatus



Dec. l2, 1933.v R. s. BLAIR RADIO RECEPTION APPARATUS original Filed Aug. 24,` 1928 2 sheets-sheet 1 INVENTOR Dec. l2, 1933. R s, BLAIR 1,938,683

RADIO RECEPTION APPARATUS Original Filed Aug. 24, 1928 2 Sheets-Sheet 2 J4 32, 7J; j

J/ 7J fig. JJ 30 42* 27 J4 7% JH fzi 26 k 20 @am INVENTOR Patented Dec. 12, 1933 UNITED. STATES PATENT OFFICE Application August 24, 1928, Serial No. 301,899 Renewed October 7, 1931 12 Claims.

This invention relates to radio reception apparatus and more particularly to arrangements of such apparatus as permit a limited use by each of a considerable'number of stations at I will with a single general receiving installation.

One of the objects thereof is to provide-practical apparatus of the above nature of simple and durable construction. Another object is to provide apparatus of the above nature of eilicient and dependable action. Other objects are to provide apparatus of the above nature which shall be substantially automatic in action and which shall give eiective service and be substantially proof Vagainst misuse. Other objects will be in part obvious and in part pointed out hereinafter. 1

The invention accordingly consistsin the features of construction, combinations of elements,v and arrangement of parts as will be exempliiled in the structure to be hereinafter described and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one of the, various possible embodiments of this invention,

Figure 1 is a sectional elevation of a controlling mechanism taken substantially along the line 1`1 of Fig. 2;

Fig. 2 is an end elevation'of the device shown in Fig. 1;

Fig. 3 is a sectional view of certain parts shown in Fig. l in another position;

Fig. 4 is a sectional elevation taken along the line 4-4 of Fig. 1;

Fig. 5 is a diagrammatic plan of a system; and

Fig. 6 is a diagrammatic detailed view of an automatic controlling device.

Similar reference characters refer to similar l parts throughout the several views of the drawings.

Referring now to Fig. 5 of these drawings, there is shown diagrammatically a number of receiving mechanisms 10, 11, 12, and 13 which may be respectively provided with serials or loops 14, 15, 16, and 17. These receiving mechanisms may be of any well-known type respectively adapted to send out along the wires 18, 19, 20, and 21 an electric current of such wave form and other characteristics as is adapted to actuate an ordinary loud speaker. These several wires may be provided with a common return wire 22, or, if desired, a complete and separate metallic circuit may be used for each.

At 23 and 24 are shown two of a number of stations, it being understood that a large number of these stations is contemplated corresponding, for example, to the rooms of a hotel. As the apparatus at each station is identical, that at one only will be described in detail.

A loud speaker 25 is provided with a connection 26 to a manual switch 27 which may be swung at will to make connection as indicated with any of the wires 18, 19, 20, and 21. The completion of the circuit, however, with the chosen receiving apparatus 16, 11, 12, or 13, and the duration of its completion depends upon the mechanism shown more in detail in Figs. 1, 2, and 3 of the drawings.

A metallic casing 28 has mountedthereon by i1 sulating supports 29 a pair of resilient contact members 30 and 31. These contact members, as best shown in Fig. 5 of the drawings, are respectively connected by wires 32 and 33 with the loud speaker 25 and with an electromagnet 34, while the casing 28 is connected by wire 35 with the return circuit 22.

The circuit through magnet 34 leads through conductors 36 and 37 to a local battery 38 at the receiving station, and thence to a plate 39 'having thirteen exposed contacts 40 coacting with a rotary contact arm 41 which is insulated from the plate and connected by conductor 42 g with the conductor 22. Diagrammatically indicated at 43 is clockwork by which the arm 41 is so driven as to makeengagement with one of the contacts 40 f or ve minutes. It will be seen that in this manner there is an electrical impulse sent through the electromagnet 34 from the battery 38 each iive minutes so long as the circuit is completed from the contact 31 to the casing 28.

Recurring to Fig. 1 of the drawings, it will be seen that the magnet 34 is provided with a movable core 44 to which is pivoted a pawl member 45 having its free end urged downwardly by a compression spring 46 mounted between an arm 47 on the pawl member and a -guide member 48' through which the core passes. The pawl 45 coacts with a ratchet 49 mounted upon a shaft 50 and provided with thirteen teeth. This ratchet is also provided with a roller 51 urged by a nat spring 52 between the teeth in such'. manner as to cause the ratchet to move throughout a complete tooth at each actuation.

Also mounted upon the shaft 50 is a cam 53 having a projection 54 coacting with'a projection 55 upon a locking member 56 pivotally mounted at 57 upon one wall of a coin chute 58. This locking member 56 is normally held by the projection 54 in the position shown in Fig. 1 of the drawings, although the flat spring 59 tends to swing its lower end outwardly in the direction of the ratchet. The locking member is provided with a pair of projections 60 and 61 passing through openings .in the adjacent wall of the coin chute 58, themember 61 in 'the position shown in Fig. 1 being adapted to obstruct the passage of coins through the chute.

The upper end of chute 58 is preferably provided with the usual aring part 62, and it leads at its lower end into a coin collection box 63. y

Turning again to Fig. 5 of the drawings, there is diagrammatically indicated in connection with each of the receiving devices 10, 11, 12, and 13 a movable part 64 which is the volumeor power-control of the particular receiving apparatus with which it is associated. Each of these power-control members is governed by an assocated electromagnet 65. Each electromagnet 65, as shown in Fig. 6 of the drawings, preferably controls a pilot resistance 66 which may be in the form of a carbon pile as indicated. Thus, as the average current through the coil 65 increases, the resistance of the element 66 is increased by a separation of its component members. The resistance device 66 is connected in a local circuit 67 comprising a local battery 68 and a coil 69 governing the spring-retracted member 64 which may be the ordinary powercontrol device of the receiving apparatus, as above noted. By this arrangement, if the average or aggregate current through the coil 65 weakens, due for example to the connection of a large number of loud speakers on that particular circuit, then the value of the resistance 66 will decrease due to compression, and the electromagnet 69 be correspondingly increased. The latter causes movement of the power-control element 64 in such direction as to increase the power output of the corresponding receiving apparatus and bring the action of each of the loud speakers up to normal volume. By a reverse action, if the number of loud speakers connected on any particular receiving apparatus is abnormally low, the electromagnet 65 corresponding thereto will be abnormally strong, weakening resistance 66 and magnet 69, and cutting down the output of the receiving apparatus connected therewith.

Considering now the action of the apparatus as a whole, and assuming it to be in the normal inoperative state indicated in Fig. 1 of the drawings, if it be desired at any station, for example a hotel room, to place in operation the loud speaker there located, a coin, indicated at '70, is dropped in the coin chute and rests against the shoulder 61. This coin, coacting with slight bends or projections 71 in the contact members 3Q and 31, connects the latter with the metallic casing 28 and with the return circuit 22, it being understood that the switch 27 is swung to make connection with the desired receiving apparatus, and as the latter are each attuned to the output of a suitable sending station, the desired sending or broadcasting station may be selected. The loud speaker is thus placed in circuit by the connection through the metallic coin from contact 30 to the part 28, and in like manner connection is made between the contact 31 and the casing 28. Thereafter, whenever the contact arm 41 engages a contact 40, an impulse will be transmitted through the magnet 34 and the cam 53 turned throughout one-thir- Y teenth of a revolution. The rst movement of cam 53 releases the projecting part 55, and the spring 59 swings the locking member 56 into the position shown in Fig. 3 of the drawings. In this position the projection 61 is removed from beneath the coin, permitting it to fall into the reception box 63, and the upper projection 60 is swung into the chute and against the two contact members 30 and 31. This projecting part 60 is preferably bifurcated to provide the Separate arms 72 each having an edge 73. In vthis manner, if a number of coins are inserted within the slot edge to edge, they will not prevent the swinging inwardly of the stop 60 whose prongs 72, being offset from the center line of the coins, can enter therebetween.

The apparatus remains in the condition above described until a predetermined number of impulses has been sent through the electromagnet 34, at which time the cam projection 54 will engage the lug 55 and swing it inwardly against the spring 59 so as to restore the parts in the position shown in Fig. 1 of the drawings. Unless another coin is then or has been inserted in the chute, the loud speaker will be automatically disconnected and the energization of magnet 34 prevented, for the contacts 30 and 31 are then free from connection with the ground circuit 28 either through the metallic coin or through the metallic locking member 56 which takes the place of a coin as its upper end 60 is swung inwardly.

For purposes of illustration it has been assumed that the ratchet 49 is actuated throughout one tooth for ve minutes, thus assuring a connection of one hour or slightly in excess thereof.

It may here be noted that the receiving mechanisms 10, 11, 12, and 13 and apparatus associated therewith preferably forms in effect the central station, and it is to be understood that the term central is used throughout in the following claims to indicate the characteristic by virtue of which one group of apparatus is adapted to supply a substantial number of relatively isolated loud speakers. It is also to be understood that the term speaker station is used to denote one of a number of installations adapted to coact with a central station and deliver in audible form the output of radio received at the central station.

As many possible embodiments may be made of the above invention and as many changes might. be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown inthe accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In radio receiving apparatus, in combination, a plurality of speaker stations, a central time-controlling apparatus, receiving apparatus, coin-controlled means at each station adapted to connect said receiving apparatus to its speaker, and means controlled by said time-controlled apparatus adapted at a substantially predetermined time thereafter to disconnect the same.

2. In radio receiving apparatus, in combination, a plurality of speaker stations, a. central time-controlling apparatus adapted to send electric impulses to said stations at regular intervals of'time, receiving apparatus, means at each station adapted tov connect said receiving apparatus to its speaker, and means at each station actuated by said impulses adapted at a substantially predetermined time thereafter to disconnect said speaker from said receiving apparatus.

3. In radio receiving apparatus, in combination, a plurality of `speaker stations, a central `time-controlling apparatus adapted to send electric impulses to said stations 'at regularintervals of time, receiving apparatus, means at each station adapted to connect said receiving apparatus to its speaker, and means at each station actuated by said impulses adapted at a substantially predetermined time thereafter to disconnect said speaker from said receiving apparatus, said last means comprising mechanism adapted to'be moved by said impulses tlrst into a position to maintain connection and thereafter into a position to break connection.

4. In radio receivingapparatus, in combination, a plurality of speaker stations, a central `time-controlling apparatus, receiving apparatus,

and means controlling the same in accordance with the number of stations, connected and adapted automatically to tend to maintain the loudness and delivery at each station substantially constant.

6. In radio receiving apparatus, in combination, a plurality of speaker stations, central receiving apparatus, means adapted to connect said receiving apparatus with each of said speaker stations, mechanism at said receiving apparatus adapted -to increase the power of output of said receiving apparatus, and means conjointly controlled by said speaker stations connected to said mechanism and adapted to increase its power of delivery in accordance with the number of stations connected thereto.

7. In radio receiving apparatus, in combination, a plurality of speaker stations, a plurality of receiving apparatuses located at a central station, a central time-controlling apparatus, means leading from each receiving apparatus and from said time-controlling apparatus to each speaker station, means adapted to'connect at will each of said speaker stations to any o! said receiving apparatuses in parallel withv other speaker stations, and means controlled from said time-controlled apparatus adapted automatically to disconnect said speaker stations at a substantially predetermined time after their connection..

8. In radio receiving apparatus, in combination, a plurality of speaker stations, a central time-controlled apparatus. a central receiving apparatus, coin-controlled means at said speaker stations adapted to make connection with said time-controlled apparatus and said receiving apparatus, and means at each station controlled from said central time-controlled apparatus adapted to maintain said connection for a substantially predetermined length of time and automatically to disconnect the same thereafter.

9. In radio receiving apparatus, in combina. tion, a plurality of speaker stations, a central time-controlling apparatus, receiving apparatus, means at each station adapted to connect said receiving apparatus to its speaker, means controlled by said time-controlled apparatus adapted at a substantially predetermined time thereafter to disconnect the same, and means controlling said receiving` apparatus in accordance with the number of speaker stations connected thereto adapted automatically to control the power of delivery of said receiving apparatus substantially in accordance with the number of said connected stations'.

10. In radio receiving apparatus, in combination, a plurality of speaker stations, central timecontrolled apparatus adapted to send out electrical impulses at substantially regular intervals of time, central receiving apparatus, coin-controlled means at said speaker stations adapted to connect the speaker thereat to said receiving apparatus, mechanism at each of said speaker stations connected with and susceptible to said electrical impulses, and means controlled by said mechanism adapted to maintain said connection throughout a predetermined number of said impulses and automatically break said connection thereafter.

11. In radio receiving apparatus, in combination, a plurality of speaker stations, a central time-controlled apparatus, a central receiving apparatus, coin-controlled means at said speaker sections adapted to make connection with said time-controlled apparatus and said receiving apparatus, means at each station controlled from said' central time-controlled apparatus adapted to maintain said connection for a substantially predetermined length of time and automatically to disconnect the `same thereafter, and mechanism at said receiving apparatus adapted automatically to vary its power of delivery substantially in accordance with the number of stations connected therewith.

12. I n radio receiving apparatus, in combination, a speaker, a receiving device adapted to be connected with said speaker and render the same operative, a coin-controlled device compris-V ing a member adapted to be moved by the coin, timing apparatus, means comprising a circuit controlled by movement oi' said member adapted to connect said speaker with said receiving device and adapted to render operative said timing apparatus, a rotary member, means controlled by said timing apparatus adapted to rotate said member with a series of intermittent movements, means controlled by said rotary member adapted upon movement from its initial position to hold said connections in closed circuit independently of the coin and adapted upon a com- V12o i 

